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1.
J Pathol ; 252(2): 101-113, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32617978

RESUMEN

The histone demethylase KDM4B functions as a key co-activator for the androgen receptor (AR) and plays a vital in multiple cancers through controlling gene expression by epigenetic regulation of H3K9 methylation marks. Constitutively active androgen receptor confers anti-androgen resistance in advanced prostate cancer. However, the role of KDM4B in resistance to next-generation anti-androgens and the mechanisms of KDM4B regulation are poorly defined. Here we found that KDM4B is overexpressed in enzalutamide-resistant prostate cancer cells. Overexpression of KDM4B promoted recruitment of AR to the c-Myc (MYC) gene enhancer and induced H3K9 demethylation, increasing AR-dependent transcription of c-Myc mRNA, which regulates the sensitivity to next-generation AR-targeted therapy. Inhibition of KDM4B significantly inhibited prostate tumor cell growth in xenografts, and improved enzalutamide treatments through suppression of c-Myc. Clinically, KDM4B expression was found upregulated and to correlate with prostate cancer progression and poor prognosis. Our results revealed a novel mechanism of anti-androgen resistance via histone demethylase alteration which could be targeted through inhibition of KDM4B to reduce AR-dependent c-Myc expression and overcome resistance to AR-targeted therapies. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Adenocarcinoma/metabolismo , Resistencia a Antineoplásicos/fisiología , Histona Demetilasas con Dominio de Jumonji/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Adenocarcinoma/patología , Antagonistas de Receptores Androgénicos/farmacología , Animales , Línea Celular Tumoral , Proliferación Celular/fisiología , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Neoplasias de la Próstata Resistentes a la Castración/patología , Proteínas Proto-Oncogénicas c-myc/metabolismo
2.
Cancer Sci ; 111(5): 1567-1581, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32133742

RESUMEN

The histone demethylase lysine-specific demethylase 4A (KDM4A) is reported to be overexpressed and plays a vital in multiple cancers through controlling gene expression by epigenetic regulation of H3K9 or H3K36 methylation marks. However, the biological role and mechanism of KDM4A in prostate cancer (PC) remain unclear. Herein, we reported KDM4A expression was upregulation in phosphatase and tensin homolog knockout mouse prostate tissue. Depletion of KDM4A in PC cells inhibited their proliferation and survival in vivo and vitro. Further studies reveal that USP1 is a deubiquitinase that regulates KDM4A K48-linked deubiquitin and stability. Interestingly, we found c-Myc was a key downstream effector of the USP1-KDM4A/androgen receptor axis in driving PC cell proliferation. Notably, upregulation of KDM4A expression with high USP1 expression was observed in most prostate tumors and inhibition of USP1 promotes PC cells response to therapeutic agent enzalutamide. Our studies propose USP1 could be an anticancer therapeutic target in PC.


Asunto(s)
Antineoplásicos/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Histona Demetilasas con Dominio de Jumonji/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Proteasas Ubiquitina-Específicas/antagonistas & inhibidores , Animales , Antineoplásicos/farmacología , Benzamidas , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Inhibidores Enzimáticos/farmacología , Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Histona Demetilasas con Dominio de Jumonji/genética , Masculino , Ratones , Ratones Mutantes , Nitrilos , Fosfohidrolasa PTEN/deficiencia , Feniltiohidantoína/análogos & derivados , Feniltiohidantoína/farmacología , Feniltiohidantoína/uso terapéutico , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Unión Proteica/efectos de los fármacos , Estabilidad Proteica/efectos de los fármacos , Proteínas Proto-Oncogénicas c-myc/genética , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Transducción de Señal/efectos de los fármacos , Proteasas Ubiquitina-Específicas/genética , Proteasas Ubiquitina-Específicas/metabolismo , Ubiquitinación/efectos de los fármacos
3.
Curr Opin Oncol ; 28(3): 241-7, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26907571

RESUMEN

PURPOSE OF REVIEW: Prostate cancer (PCa) demonstrates characteristic changes in metabolism and bioenergetics in the transition from benign to malignant tissue. It is feasible that some of these changes may be targetable for therapeutic purposes. This review will highlight some of the current metabolically targeted therapies being investigated for the treatment of prostate cancer. RECENT FINDINGS: The transition from benign to malignant prostate cells is characterized by decreased intracellular zinc concentration and subsequent release of inhibition of the tricarboxylic acid cycle enzyme m-aconitase, which leads to the decrease in citrate concentration within the cancer tissue. Instead of the largely glycolytic phenotype exhibited by most cancers, PCa relies on glutamine and lipids for survival and proliferation. Early studies are beginning to demonstrate that targeting some of the upregulated pathways with inhibitors of key enzymes, such as glutaminase, fatty acid synthase, 3-hydroxy-3-methylglutaryl-coenzyme A reductase, hexokinase, zinc transport, or complex I in the mitochondria may have significant metabolic effects and therapeutic potential. SUMMARY: The unique metabolic profile of PCa allows for many potential avenues of treatment. Future studies will continue to test if the metabolic characterization and treatment of PCa could be an important approach to provide personalized treatment for the disease.


Asunto(s)
Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Animales , Humanos , Masculino , Terapia Molecular Dirigida , Medicina de Precisión/métodos
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 482-6, 2016 Feb.
Artículo en Zh | MEDLINE | ID: mdl-27209754

RESUMEN

Simulated water samples of 3 kinds of preservatives and 4 kinds of sweeteners were formulated by using orthogonal design. Kernel independent component analysis (KICA) was used to process the UV spectra of the simulated water samples and the beverages added different amounts of the additive standards, then the independent components (ICs), i. e. the UV spectral profiles of the additives, and the ICs' coefficient matrices were used to establish UV-KICA-SVR prediction model of the simulated preservatives and sweeteners solutions using support vector regression (SVR) analysis. The standards added beverages samples were obtained by adding different amounts level of additives in carbonated beverages, their UV spectra were processed by KICA, then IC information represented to the additives and other sample matrix were obtained, and the sample background can be deducted by removing the corresponding IC, other ICs' coefficient matrices were used to estimate the amounts of the additives in the standard added beverage samples based on the UV-KICA-SVR model, while the intercept of linear regression equation of predicted amounts and the added amounts in the standard added samples is the additive content in the raw beverage sample. By utilization of chemometric "blind source separation" method for extracting IC information of the tested additives in the beverage and other sample matrix, and using SVR regression modeling to improve the traditional standard addition method, a new method was proposed for the screening of the preservatives and sweeteners in carbonated beverages. The proposed UV-KICA-SVR method can be used to determine 3 kinds of preservatives and 4 kinds of sweetener in the carbonate beverages with the limit of detection (LOD) are located with the range 0.2-1.0 mg · L⁻¹, which are comparable to that of the traditional high performance liquid chromatographic (HPLC) method.


Asunto(s)
Bebidas Gaseosas/análisis , Conservantes de Alimentos/análisis , Edulcorantes/análisis , Análisis Espectral , Máquina de Vectores de Soporte
5.
J Neurooncol ; 110(3): 315-23, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23011120

RESUMEN

SF188/V+ is a highly vascular human glioma model that is based on transfection of vascular endothelial growth factor (VEGF) cDNA into SF188/V- cells. This study aims to assess its growth and vascularity properties in vivo in a rat model. Thirty-two adult rats were inoculated with SF188/V+ tumor cells, and, for comparison, five were inoculated with SF188/V- tumor cells. Several conventional magnetic resonance imaging (MRI) sequences were acquired, and several quantitative structural (T(2) and T(1)), functional [isotropic apparent diffusion coefficient (ADC) and blood flow], and molecular [protein and peptide-based amide proton transfer (APT)] MRI parameters were mapped on a 4.7 T animal scanner. In rats inoculated with SF188/V+ tumor cells, conventional T(2)-weighted images showed a highly heterogeneous tumor mass, and post-contrast T(1)-weighted images showed a heterogeneous, strong enhancement of the mass. There were moderate increases in T(2), T(1), and ADC, and large increases in blood flow and APT in the tumor, compared to contralateral brain tissue. Microscopic examination revealed prominent vascularity and hemorrhage in the VEGF-secreting xenografts as compared to controls, and immunohistochemical staining confirmed increased expression of VEGF in tumor xenografts. Our results indicate that the SF188/V+ glioma model exhibits some MRI and histopathology features that closely resemble human glioblastoma.


Asunto(s)
Neoplasias Encefálicas/patología , Proliferación Celular , Modelos Animales de Enfermedad , Glioma/patología , Imagen por Resonancia Magnética , Neovascularización Patológica , Animales , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Glioma/diagnóstico por imagen , Glioma/genética , Humanos , Masculino , Radiografía , Ratas , Ratas Desnudas , Células Tumorales Cultivadas/trasplante , Factor A de Crecimiento Endotelial Vascular/genética
6.
Med Phys ; 38(6): 2892-903, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21815364

RESUMEN

PURPOSE: In the radiopharmaceutical therapy approach to the fight against cancer, in particular when it comes to translating laboratory results to the clinical setting, modeling has served as an invaluable tool for guidance and for understanding the processes operating at the cellular level and how these relate to macroscopic observables. Tumor control probability (TCP) is the dosimetric end point quantity of choice which relates to experimental and clinical data: it requires knowledge of individual cellular absorbed doses since it depends on the assessment of the treatment's ability to kill each and every cell. Macroscopic tumors, seen in both clinical and experimental studies, contain too many cells to be modeled individually in Monte Carlo simulation; yet, in particular for low ratios of decays to cells, a cell-based model that does not smooth away statistical considerations associated with low activity is a necessity. The authors present here an adaptation of the simple sphere-based model from which cellular level dosimetry for macroscopic tumors and their end point quantities, such as TCP, may be extrapolated more reliably. METHODS: Ten homogenous spheres representing tumors of different sizes were constructed in GEANT4. The radionuclide 131I was randomly allowed to decay for each model size and for seven different ratios of number of decays to number of cells, N(r): 1000, 500, 200, 100, 50, 20, and 10 decays per cell. The deposited energy was collected in radial bins and divided by the bin mass to obtain the average bin absorbed dose. To simulate a cellular model, the number of cells present in each bin was calculated and an absorbed dose attributed to each cell equal to the bin average absorbed dose with a randomly determined adjustment based on a Gaussian probability distribution with a width equal to the statistical uncertainty consistent with the ratio of decays to cells, i.e., equal to Nr-1/2. From dose volume histograms the surviving fraction of cells, equivalent uniform dose (EUD), and TCP for the different scenarios were calculated. Comparably sized spherical models containing individual spherical cells (15 microm diameter) in hexagonal lattices were constructed, and Monte Carlo simulations were executed for all the same previous scenarios. The dosimetric quantities were calculated and compared to the adjusted simple sphere model results. The model was then applied to the Bortezomib-induced enzyme-targeted radiotherapy (BETR) strategy of targeting Epstein-Barr virus (EBV)-expressing cancers. RESULTS: The TCP values were comparable to within 2% between the adjusted simple sphere and full cellular models. Additionally, models were generated for a nonuniform distribution of activity, and results were compared between the adjusted spherical and cellular models with similar comparability. The TCP values from the experimental macroscopic tumor results were consistent with the experimental observations for BETR-treated 1 g EBV-expressing lymphoma tumors in mice. CONCLUSIONS: The adjusted spherical model presented here provides more accurate TCP values than simple spheres, on par with full cellular Monte Carlo simulations while maintaining the simplicity of the simple sphere model. This model provides a basis for complementing and understanding laboratory and clinical results pertaining to radiopharmaceutical therapy.


Asunto(s)
Linfoma/patología , Linfoma/radioterapia , Modelos Biológicos , Radiofármacos/uso terapéutico , Animales , Ácidos Borónicos/uso terapéutico , Bortezomib , Radioisótopos de Yodo/uso terapéutico , Ratones , Método de Montecarlo , Pirazinas/uso terapéutico , Radiometría
7.
Anal Bioanal Chem ; 394(3): 827-33, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19333581

RESUMEN

A method is proposed for monitoring the radix rehmanniae proparate processing procedure and determining the endpoint of the process using attenuated total reflectance (ATR) FT-IR through nonnegative independent component analysis (ICA). In the proposed method, ATR FT-IR spectra of the samples were firstly measured at different steaming periods. Then, nonnegative ICA was used for direct estimation of the feature spectra of the pure components in the mixture without pre-separation and other prior information. The estimated independent components (ICs) and their variation of the relative concentrations were used to characterize the processing procedure and determine the endpoint. The results show that the estimated three ICs are consistent with that of the chemical components in the mixtures, i.e. catalpol/rehmaionoside, glucose, and other compounds that nearly keep invariant during the processing procedure. The endpoint determined by the IR-ICA method is 15 h, which was located in the range obtained by expert sensory analysis, whereas the endpoint determined by the traditional sensory analysis is 14-17 h and even 14-20 h, which showed the significant deviation of the endpoints determined by different operators.


Asunto(s)
Análisis de Componente Principal/métodos , Rehmannia/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Reproducibilidad de los Resultados , Factores de Tiempo
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(12): 3392-4, 2009 Dec.
Artículo en Zh | MEDLINE | ID: mdl-20210177

RESUMEN

The Huai radix rehmanniae at different grades was pretreated by wet digestion, and then the metal elements in the radix rehmanniae and the prepared sample by steaming method were determined using ICP-MS. The results indicate that there is no obvious difference in the metal elements between the different grades and between the dried radix rehmanniae and its corresponding prepared product. There are elements Zn, Cu, Cr, Fe, Mn, Sn, Ni, Mo, Go, etc. in radix rehmanniae, among which the contents of Ca, Fe, Al, Zn and Cu are higher; the metal elements beneficial to human body in dried radix rehmanniae are relative lower than that in the prepared one. The elements such as Co, Ni, Cr, Mn, etc. in radix rehmanniae have poison effects on human body when their contents are more than a certain threshold value, although they are human essential elements. Element Pb is harmful to human body, which should be controlled and reduced/eliminated in the processing procedure. The determination and comparison of the metal elements in radix rehmanniae at different grades can provide useful information about the comprehensive evaluation of dried radix rehmanniae and their prepared products.


Asunto(s)
Espectrometría de Masas , Metales/análisis , Rehmannia/química , Oligoelementos/análisis
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(9): 2383-7, 2009 Sep.
Artículo en Zh | MEDLINE | ID: mdl-19950634

RESUMEN

The catalpol, which can be isolated from the Chinese traditional herbs Rehmannia glutinosa as an effective and active ingredient, is an iridoid glycoside with many pharmacological functions. The molecular structure and the infrared (IR) spectrum of catalpol were calculated using density-functional theory (B3LYP) at 6-311G** level, and the theoretical frequency was scaled by 0. 96. The vibrational modes of IR spectrum were assigned and compared with that of the experimental data. The calculated IR spectral features from DFT are in good agreement with the experimental ones. The results indicate that DFT is an useful method for the structure optimization and IR spectrum calculation of the iridoid compounds, which can be isolated from natural resources and often with difficulty. The theoretical calculation results of IR spectrum can provide useful information for the prediction of the theoretical property and investigation of the structure-activity relationship of the iridoid compounds.


Asunto(s)
Glucósidos Iridoides/análisis , Espectrometría Raman , Modelos Teóricos , Estructura Molecular , Rehmannia/química , Espectroscopía Infrarroja por Transformada de Fourier , Relación Estructura-Actividad , Vibración
10.
Clin Cancer Res ; 13(5): 1453-8, 2007 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-17332288

RESUMEN

PURPOSE: EBV and other herpesviruses are associated with a variety of malignancies. The EBV thymidine kinase (TK) is either not expressed or is expressed at very low levels in EBV-associated tumors. However, EBV-TK expression can be induced in vitro with several chemotherapeutic agents that promote viral lytic induction. The goal of this study is to image EBV-associated tumors by induction of viral TK expression with radiolabeled 2'-fluoro-2'-deoxy-beta-D-5-iodouracil-arabinofuranoside (FIAU). EXPERIMENTAL DESIGN: Immunoblot, luciferase reporter assay, and in vitro assay with [(14)C]FIAU were used to show the effects of bortezomib on the induction of lytic gene expression of EBV-associated tumor cells. In vivo imaging and ex vivo biodistribution studies with [(125)I]FIAU on EBV-associated tumors were done to visualize and confirm, respectively, the EBV(+) tumor-specific effects of bortezomib. RESULTS: In vitro assays with [(14)C]FIAU and ex vivo biodistribution studies with [(125)I]FIAU showed that uptake and retention of radiolabeled FIAU was specific for cells that express EBV-TK. Planar gamma imaging of EBV(+) Burkitt's lymphoma xenografts in severe combined immunodeficient mice showed [(125)I]FIAU localization within tumors following treatment with bortezomib. CONCLUSIONS: These results indicate the feasibility of imaging chemotherapy-mediated viral lytic induction by radiopharmaceutical-based techniques such as single photon emission computed tomography and positron emission tomography.


Asunto(s)
Arabinofuranosil Uracilo/análogos & derivados , Linfoma de Burkitt/diagnóstico por imagen , Diagnóstico por Imagen , Genes Virales , Radiofármacos , Timidina Quinasa/genética , Animales , Antineoplásicos/uso terapéutico , Ácidos Borónicos/uso terapéutico , Bortezomib , Linfoma de Burkitt/tratamiento farmacológico , Linfoma de Burkitt/virología , Expresión Génica , Técnicas de Transferencia de Gen , Herpesvirus Humano 4/enzimología , Herpesvirus Humano 4/genética , Humanos , Immunoblotting , Ratones , Neoplasias Experimentales/diagnóstico por imagen , Neoplasias Experimentales/tratamiento farmacológico , Virus Oncogénicos/enzimología , Virus Oncogénicos/genética , Pirazinas/uso terapéutico , Cintigrafía , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Timidina Quinasa/metabolismo
11.
Transl Androl Urol ; 7(Suppl 4): S490-S497, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30363493

RESUMEN

Prostate cancer treatment is based on the stratification of disease as low-, intermediate- or high-risk. This stratification has been largely based on anatomic pathology of the disease, as well as through the use of prostate specific antigen (PSA). However, despite this stratification, there remains heterogeneity within the current classification schema. Utilizing a metabolic approach may help to further establish novel biomolecular markers of disease aggressiveness. These markers may eventually be useful in not only the diagnosis of disease but in creating tumor specific targeted therapy for improved clinical outcomes.

12.
Transl Androl Urol ; 7(5): 855-863, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30456188

RESUMEN

Approximately 25% of the 2 million new cancer diagnoses in the United States in 2018 were comprised of malignancies of the urogenital system. Of these cancers, 75% occurred in the kidney/renal pelvis, prostate, and urinary bladder. Early diagnosis is beneficial to long-term survival. Currently, urologists rely heavily on computed tomography (CT), magnetic resonance imaging (MRI), ultrasound (US), and positron emission tomography (PET) to both diagnose and offer prognoses, but these techniques are limited in their resolution and are more effective when cancers have reached macroscopic size in later stages. Recent developments in cancer metabolomics have revealed that cancerous cells preferentially upregulate specific metabolic pathways as a means of conserving their resources and maximizing their growth potential. This has opened a new avenue for early diagnosis with much higher resolution, reliability, and accuracy through 13C hyperpolarized MRI. Preferential cancer pathways can be elucidated through this technique using 13C-labeled molecules utilized for energy generation and tumor growth. As these pathways are identified, targeted therapies are being designed to inhibit these pathways to allow for treatment that is cytotoxic to malignant cells but preserves native cells. In this paper, we review the current understanding of urologic cancer metabolomics, specifically in the kidney, prostate, and bladder. We will review the basic physics of MRI and demonstrate how hyperpolarized 13C MRI offers an innovative solution to early diagnosis as well as creates novel avenues for more targeted therapy.

13.
Oncoimmunology ; 4(3): e991228, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25949910

RESUMEN

Cleavage or shedding of the surface antigen, MHC class I chain-related (MIC) protein (A/B) has been known to be one of the mechanisms by which tumor cells escape host immune surveillance. Thus, any strategy to augment the surface expression of MICA/B could facilitate anticancer immune response. Here, we demonstrate that metabolic perturbation by the glycolytic inhibitor, 3-bromopyruvate (3-BrPA) augments the surface expression of MICA/B in human breast cancer cell lines, MDA-MB-231 and T47D. Data from in vitro studies show that a non-toxic, low-dose of 3-BrPA is sufficient to perturb energy metabolism, as evident by the activation of p-AMPK, p-AKT and p-PI3K. Further, 3-BrPA-treatment also elevated the levels of MICA/B in human breast cancer cell lines. Significantly, 3-BrPA-dependent increase in MICA/B levels also enhanced the sensitivity of cancer cells to natural killer (NK-92MI)-mediated cytotoxicity. In vivo, 3-BrPA-pretreated cells demonstrated greater sensitivity to NK-92MI therapy than their respective controls. The antitumor effect was confirmed by a reduction in tumor size and decreased tumor viability as observed by bioluminescence imaging. Histological examination and TUNEL staining demonstrated that NK-92MI administration promoted apoptosis in 3-BrPA-pretreated cells. Taken together, our data show that targeting energy metabolism could be a novel strategy to enhance the effectiveness of anticancer immunotherapeutics.

14.
Artículo en Inglés | MEDLINE | ID: mdl-24810027

RESUMEN

White chrysanthemum flower is one of the most popular plants found everywhere in China and used as herbs. In the present work, three-dimensional fluorescence technique was used to discriminate species of white chrysanthemum flowers. Parameters affecting extraction efficiency were investigated. Under the optimal conditions, the three-dimensional fluorescence characteristics of three types of white chrysanthemum flowers were obtained. It was found that there were two main fluorescence peaks with remarkable difference in fluorescence intensity, one was corresponding to flavonoids and another was attributed to chlorophyll-like compounds. There were remarkable differences among the contours of the three white chrysanthemum flowers. Further studies showed that the fluorescence intensity ratios of chlorophyll-like compounds to flavonoids had a certain relationship with the species; those for Huai, Hang and Huangshan white chrysanthemum flowers were 6.9-7.4, 18.9-21.4 and 73.6-84.5, respectively. All of the results suggest that three-dimensional fluorescence spectra can be used for the discrimination of white chrysanthemum flowers with the advantages of low cost, ease for operation and intuition.


Asunto(s)
Clorofila/química , Chrysanthemum/química , Flores , Espectrometría de Fluorescencia , Medicamentos Herbarios Chinos/análisis , Flavonoides/química , Fluorescencia , Imagenología Tridimensional , Control de Calidad , Solventes/química , Especificidad de la Especie , Temperatura , Factores de Tiempo
15.
Sci Rep ; 4: 6816, 2014 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-25351825

RESUMEN

Lack of an in vitro model of metastasis has been a major impediment in understanding the molecular regulation of metastatic processes, and identification of specific therapeutic targets. We have established an in vitro model which displayed the signatures of metastatic phenotype such as migration, invasiveness, chemoresistance and expression of cancer stem-cell markers. This in vitro model was developed by the induction of reversal of multicellular spheroids that were generated by anchorage-independent growth. In vivo data further validated the metastatic phenotype of the in vitro model. Besides delineating the molecular events of metastasis, this model could also improve the screening efficiency of antimetastatic agents.


Asunto(s)
Neoplasias/patología , Animales , Antineoplásicos/farmacología , Biomarcadores , Técnicas de Cultivo de Célula , Modelos Animales de Enfermedad , Resistencia a Antineoplásicos , Expresión Génica , Xenoinjertos , Humanos , Técnicas In Vitro , Masculino , Ratones , Metástasis de la Neoplasia , Neoplasias/genética , Neoplasias/metabolismo , Células Madre Neoplásicas/metabolismo , Esferoides Celulares , Células Tumorales Cultivadas , Vimentina/genética , Vimentina/metabolismo
16.
ACS Med Chem Lett ; 5(4): 395-9, 2014 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-24900847

RESUMEN

Cardiac glycosides are potent inhibitors of cancer cell growth and possess antiviral activities at nanomolar concentrations. In this study we evaluated the anticytomegalovirus (CMV) activity of digitoxin and several of its analogues. We show that sugar type and sugar length attached to the steroid core structure affects its anticytomegalovirus activity. Structure-activity relationship (SAR) studies identified the l-sugar containing cardiac glycosides as having improved anti-CMV activity and may lead to better understanding of how these compounds inhibit CMV replication.

17.
Int J Radiat Oncol Biol Phys ; 83(3): e431-6, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22483739

RESUMEN

PURPOSE: Radiation necrosis is a major complication of radiation therapy. We explore the features of radiation-induced brain necrosis in the rat, using multiple MRI approaches, including T(1), T(2), apparent diffusion constant (ADC), cerebral blood flow (CBF), magnetization transfer ratio (MTR), and amide proton transfer (APT) of endogenous mobile proteins and peptides. METHODS AND MATERIALS: Adult rats (Fischer 344; n = 15) were irradiated with a single, well-collimated X-ray beam (40 Gy; 10 × 10 mm(2)) in the left brain hemisphere. MRI was acquired on a 4.7-T animal scanner at ~25 weeks' postradiation. The MRI signals of necrotic cores and perinecrotic regions were assessed with a one-way analysis of variance. Histological evaluation was accomplished with hematoxylin and eosin staining. RESULTS: ADC and CBF MRI could separate perinecrotic and contralateral normal brain tissue (p < 0.01 and < 0.05, respectively), whereas T(1), T(2), MTR, and APT could not. MRI signal intensities were significantly lower in the necrotic core than in normal brain for CBF (p < 0.001) and APT (p < 0.01) and insignificantly higher or lower for T(1), T(2), MTR, and ADC. Histological results demonstrated coagulative necrosis within the necrotic core and reactive astrogliosis and vascular damage within the perinecrotic region. CONCLUSION: ADC and CBF are promising imaging biomarkers for identifying perinecrotic regions, whereas CBF and APT are promising for identifying necrotic cores.


Asunto(s)
Amidas/metabolismo , Encéfalo/irrigación sanguínea , Encéfalo/patología , Circulación Cerebrovascular/efectos de la radiación , Imagen por Resonancia Magnética/métodos , Traumatismos Experimentales por Radiación/patología , Animales , Agua Corporal/metabolismo , Encéfalo/metabolismo , Encéfalo/efectos de la radiación , Circulación Cerebrovascular/fisiología , Medios de Contraste , Imagen de Difusión por Resonancia Magnética/métodos , Gadolinio , Masculino , Necrosis , Protones , Traumatismos Experimentales por Radiación/metabolismo , Ratas , Ratas Endogámicas F344
18.
Nat Med ; 17(1): 130-4, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21170048

RESUMEN

It remains difficult to distinguish tumor recurrence from radiation necrosis after brain tumor therapy. Here we show that these lesions can be distinguished using the amide proton transfer (APT) magnetic resonance imaging (MRI) signals of endogenous cellular proteins and peptides as an imaging biomarker. When comparing two models of orthotopic glioma (SF188/V+ glioma and 9L gliosarcoma) with a model of radiation necrosis in rats, we could clearly differentiate viable glioma (hyperintense) from radiation necrosis (hypointense to isointense) by APT MRI. When we irradiated rats with U87MG gliomas, the APT signals in the irradiated tumors had decreased substantially by 3 d and 6 d after radiation. The amide protons that can be detected by APT provide a unique and noninvasive MRI biomarker for distinguishing viable malignancy from radiation necrosis and predicting tumor response to therapy.


Asunto(s)
Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Glioma/patología , Traumatismos por Radiación/patología , Animales , Diagnóstico Diferencial , Gadolinio , Humanos , Imagen por Resonancia Magnética/métodos , Ratas
19.
Anal Chim Acta ; 679(1-2): 43-8, 2010 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-20951855

RESUMEN

A method for determination of the endpoint of the procedure for radix rehmanniae steamed was proposed based on UV spectrophotometry combination with continuous wavelet transform and kernel independent component analysis (UV-CWT-KICA). In the proposed method, the raw UV spectra of the rehmanniae samples during steamed procedure were measured. The raw UV spectral data were firstly pretreated by CWT for elimination of the noise signal and enrichment of the spectral resolution, then the independent components (ICs) were estimated from the mixed CWT coefficient matrix. The results show that the ICs are chemical significance with their relative concentrations gradually decreasing or increasing during the first steamed period, and the endpoint of the steamed procedure can be determined by inspection of the relative concentration profiles, at which the ICs should be approached maximum or minimum. Furthermore, the estimated ICs of rehmanniae samples from different areas or with different grades are similar, and the relative concentration of the similar ICs in different groups are increasing or decreasing before the first 14 h, and nearly steady or some decreasing after 16 h. Based on the variations of the relative concentration profiles of the ICs, the endpoint of the steamed procedure can be determined as 15 h, while that determined by sensory analysis is 14-20 h. The proposed UV-CWT-KICA method can avoid the higher deviations of the endpoints that were determined by sensory analysis. It provides an alternative approach for determination of the endpoint of the procedure for processing traditional Chinese medicine (TCM).


Asunto(s)
Algoritmos , Determinación de Punto Final/métodos , Análisis de Componente Principal/métodos , Rehmannia/química , Espectrofotometría Ultravioleta/métodos , Análisis de Ondículas , Medicamentos Herbarios Chinos/análisis , Calor , Raíces de Plantas/química , Reproducibilidad de los Resultados , Vapor , Factores de Tiempo
20.
Curr Pharm Des ; 14(28): 3048-65, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18991718

RESUMEN

Cancer remains an important and growing health problem. Researchers have made great progress in defining genetic and molecular alterations that contribute to cancer formation and progression. Molecular imaging can identify appropriate patients for targeted cancer therapy and may detect early biochemical changes in tumors during therapy, some of which may have important prognostic implications. Progress in this field continues largely due to a union between molecular genetics and advanced imaging technology. This review details uses of molecular-genetic imaging in the context of tumor-associated viruses. Under certain conditions, and particularly during pharmacologic stimulation, gammaherpesviruses will express genes that enable imaging and therapy in vivo. The techniques discussed are readily translatable to the clinic.


Asunto(s)
Biología Molecular/métodos , Neoplasias/diagnóstico por imagen , Infecciones Tumorales por Virus/diagnóstico por imagen , Animales , Antineoplásicos/farmacología , Sistemas de Liberación de Medicamentos , Gammaherpesvirinae/genética , Gammaherpesvirinae/metabolismo , Genes Virales , Infecciones por Herpesviridae/diagnóstico por imagen , Infecciones por Herpesviridae/genética , Humanos , Neoplasias/genética , Neoplasias/virología , Cintigrafía , Radiofármacos , Infecciones Tumorales por Virus/genética
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